You must uninstall any currently installed Flash Player before installing the beta under Linux or Mac / Windows computer. Open Firefox and type following at url box: about:plugins Install flash 10 Player on Ubuntu Visit this url and grab .deb file. Uninstall old flashplayer 9 ( if installed ): $ sudo apt-get remove flashplugin-nonfree Now, install Flash 10 (make sure Firefox is not running ): $ sudo dpkg -i install_flash_player_10_linux.deb Start firefox and type about:plugins . You should see list of plugins including Flash 10. Flash 10 64 bit Linux version However, there is no 64 bit version of Flash 10 exists for Linux systems. You can install and use Flash, Java, Real Player 32 bit plugins under 64 bit Linux Firefox version -------------------------------------------- ABOUT : Adobe flash player version 10 (code-named "Astro" ) has been released and available for download. It has many new features such as: + Visual performance improvements + 3D effects +